M'malo otsika kutentha, ntchito ya batri ya lithiamu-ion si yabwino.Nthawi zambiri mabatire a lithiamu-ion akamagwira ntchito pa -10 ° C, kuchuluka kwawo kokwanira ndi kutulutsa mphamvu ndi voteji yama terminal zidzachepetsedwa kwambiri poyerekeza ndi kutentha kwabwinobwino [6], pamene kutentha kwamadzi kumatsika mpaka -20 ° C, mphamvu yomwe ilipo ngakhale kuchepetsedwa 1/3 pa firiji 25 ° C, pamene kutentha kumaliseche ndi otsika, ena mabatire lifiyamu sangathe ngakhale mlandu ndi kutulutsa ntchito, kulowa "kufa batire" boma.
1, Makhalidwe a mabatire a lithiamu-ion pa kutentha kochepa
(1) Mkulu
Kusintha kwa khalidwe la batire ya lithiamu-ion pa kutentha kochepa ndi motere: ndi kuchepa kosalekeza kwa kutentha, kukana kwa ohmic ndi kukana kwa polarization kumawonjezeka madigiri osiyanasiyana;Mphamvu yotulutsa ya batri ya lithiamu-ion ndi yotsika kuposa kutentha kwanthawi zonse.Pamene kulipiritsa ndi kutulutsa pa kutentha kochepa, mphamvu yake yogwiritsira ntchito imakwera kapena imatsika mofulumira kusiyana ndi kutentha kwabwino, zomwe zimapangitsa kuchepa kwakukulu kwa mphamvu zake zogwiritsidwa ntchito ndi mphamvu.
(2) Mwachisawawa
Kusintha kwa machitidwe a mabatire a lithiamu-ion pa kutentha kochepa kumakhala makamaka chifukwa cha zinthu zofunika zotsatirazi.Kutentha kozungulira kumakhala kotsika kuposa -20 ℃, electrolyte yamadzimadzi imalimba, kukhuthala kwake kumawonjezeka kwambiri, ndipo ma ionic conductivity ake amachepa.Kufalikira kwa lithiamu ion muzinthu zabwino komanso zoyipa zama elekitirodi kumachedwa;Lithium ion ndizovuta kuwononga, ndipo kufalikira kwake mufilimu ya SEI kumachedwa, ndipo kusokoneza kwa ndalama kumawonjezeka.Vuto la lithiamu dendrite limakhala lodziwika kwambiri pakutentha kochepa.
2, Kuthetsa kutsika kwa kutentha kwa mabatire a lithiamu-ion
Kupanga dongosolo latsopano la electrolytic lamadzimadzi kuti likwaniritse malo otsika kutentha;Sinthani mawonekedwe abwino ndi oyipa ma elekitirodi kuti mupititse patsogolo liwiro lotumizira ndikufupikitsa mtunda wotumizira;Kuwongolera mawonekedwe abwino ndi oyipa olimba a electrolyte kuti muchepetse kusokoneza.
(1) zowonjezera za electrolyte
Kawirikawiri, kugwiritsa ntchito zowonjezera zowonjezera ndi imodzi mwa njira zothandiza kwambiri komanso zachuma zowonjezera kutentha kwa batri ndikuthandizira kupanga filimu yabwino ya SEI.Pakadali pano, mitundu yayikulu yazowonjezera ndi zowonjezera za isocyanate, zowonjezera za sulfure, zowonjezera zamadzimadzi a ionic ndi zowonjezera mchere wa lithiamu.
Mwachitsanzo, dimethyl sulfite (DMS) sulfure zochokera zina, ndi yoyenera kuchepetsa ntchito, ndi chifukwa kuchepetsa mankhwala ndi lithiamu ion kumanga ndi chofooka kuposa vinyl sulfate (DTD), kuchepetsa kugwiritsa ntchito organic zina kuonjezera mawonekedwe impedance, kumanga mokhazikika komanso bwino ma ionic madutsidwe a filimu yolakwika ya elekitirodi.Ma esters a sulfite omwe amaimiridwa ndi dimethyl sulfite (DMS) ali ndi dielectric yayikulu yosasinthasintha komanso kutentha kwapang'onopang'ono.
(2) Chosungunulira cha electrolyte
The chikhalidwe lithiamu-ion batire electrolyte ndi kupasuka 1 mol wa lithiamu hexafluorophosphate (LiPF6) mu zosungunulira wosanganiza, monga EC, PC, VC, DMC, methyl ethyl carbonate (EMC) kapena diethyl carbonate (DEC), kumene zikuchokera zosungunulira, malo osungunuka, dielectric constant, viscosity ndi kugwirizana ndi lithiamu mchere zidzakhudza kwambiri kutentha kwa batire.Pakalipano, electrolyte yamalonda ndi yosavuta kulimbitsa ikagwiritsidwa ntchito kumalo otsika kutentha kwa -20 ℃ ndi pansi, kutsika kwa dielectric kumapangitsa kuti mchere wa lifiyamu ukhale wovuta kulekanitsa, ndipo kukhuthala kwake kumakhala kwakukulu kwambiri kuti batire kukana mkati ndi kutsika. nsanja yamagetsi.Mabatire a lithiamu-ion amatha kukhala ndi magwiridwe antchito otsika kwambiri pokulitsa kuchuluka kwa zosungunulira zomwe zilipo, monga kukhathamiritsa kapangidwe ka electrolyte (EC:PC:EMC=1:2:7) kuti TiO2(B)/graphene negative elekitirodi ikhale ndi A. mphamvu ya ~ 240 mAh g-1 pa -20 ℃ ndi 0.1 A g-1 kachulukidwe pano.Kapena pangani zosungunulira zatsopano za electrolyte zotsika kutentha.Kusagwira bwino kwa mabatire a lithiamu-ion pa kutentha kochepa kumakhudzana makamaka ndi kuwonongeka kwapang'onopang'ono kwa Li + panthawi ya Li + kuyika mu electrode chuma.Zinthu zomwe zimakhala ndi mphamvu zochepa zomangiriza pakati pa Li + ndi mamolekyu osungunulira, monga 1, 3-dioxopentylene (DIOX), zitha kusankhidwa, ndipo nanoscale lithium titanate imagwiritsidwa ntchito ngati zida za elekitirodi kusonkhanitsa mayeso a batri kuti alipire kuchepetsedwa kwa kufalikira kwa coefficient ma elekitirodi pa kutentha kwambiri-otsika, kuti akwaniritse bwino otsika kutentha ntchito.
(3) mchere wa lithiamu
Pakalipano, LiPF6 ion yamalonda imakhala ndi ma conductivity apamwamba, zofunikira kwambiri za chinyezi m'chilengedwe, kusasunthika kosasunthika kwa kutentha, ndi mpweya woipa monga HF mumadzimadzi ndizosavuta kuyambitsa ngozi.Filimu yolimba ya electrolyte yopangidwa ndi lithium difluoroxalate borate (LiODFB) ndiyokhazikika mokwanira ndipo imakhala ndi kutentha kochepa komanso magwiridwe antchito apamwamba.Izi ndichifukwa choti LiODFB ili ndi zabwino zonse za lithiamu dioxalate borate (LiBOB) ndi LiBF4.
3. Mwachidule
Kutsika kwa kutentha kwa mabatire a lithiamu-ion kudzakhudzidwa ndi zinthu zambiri monga zida za electrode ndi electrolytes.Kuwongolera kwakukulu kuchokera kumagulu angapo monga zida za elekitirodi ndi electrolyte kungalimbikitse kugwiritsa ntchito ndi chitukuko cha mabatire a lithiamu-ion, komanso chiyembekezo chakugwiritsa ntchito kwa mabatire a lithiamu ndichabwino, koma ukadaulo uyenera kupangidwa ndikukwaniritsidwa pakufufuza kwina.
Nthawi yotumiza: Jul-27-2023